Multiple tabs in IE7 browser sharing the same session

We are having a web application and running in IE7 browser and user tries to login in one tab and later he tries to login with different user in different tab then same session is being referenced in both the tabs
for different users. Same is the case with the Firefox also so How to fix this issues?

Refer the below link,

Session Sharing

I hope you need to write your own pattern to solve this !!